Of the following, which is not effective for eliminating sewer odors?

• A. Hydrogen peroxide
• B. Chlorine
• C. Aeration
• D. Sulfuric acid

Answer: (D)

Odor control in sewer systems centers on removing or transforming the reduced sulfur compounds that cause the rotten-egg smell, mainly hydrogen sulfide produced under anaerobic conditions. Hydrogen peroxide and chlorine act as strong oxidizers that convert sulfides into sulfates, reducing odors, while aeration physically removes volatile sulfide by releasing it as gas and boosting oxidation with atmospheric oxygen. Sulfuric acid, however, isn’t effective for odor control. Lowering the pH shifts sulfide species toward hydrogen sulfide gas, which actually increases odor rather than reduces it, and it doesn’t oxidize sulfides to non-odorous forms. It can also cause corrosion issues. So sulfuric acid isn’t a valid odor-elimination method.